Nia (ニア, Niyah) is the tritagonist of Xenoblade Chronicles 2.
Nia was originally the Blade to Lord of Echell from Gormott Providence. Nia grew up in a wealthy household, which included her driver and his daughter, who Nia came to recognize as her sister. Nia's "sister" was always sick, and the rest of the family cared for her. Nia would study to become a proper lady to help the family. Their lives would fall apart after her driver spent his entire fortune to in search of a cure for his daughter's sickness and lost his status as lord. The family would then become drifters, with Nia's sister eventually succumbing to her illnesses. To ensure the safety of Nia, her driver forced Nia to consume the body of his daughter, turning Nia into a special type of Blade called a Flesh Eater. Her Driver would also die shortly after, leaving her alone with no family. However, Nia found the core crystal that belonged to her driver and resonated with it, becoming the Driver to Dromarch. Together they went on the run from the Indoline Praetorium, who hunt down Flesh Eaters like Nia. They were rescued by Jin, who offered her to join his organization, Torna.
During a salvaging mission with Jin, Malos, and Rex, they all uncover the Ancient Ship that Addam sank under the Cloud Sea 500 years prior to keep the Aegis from wreaking havoc. She witnesses Jin kill Rex after touching the Aegis sword, prompting her and Dromarch to defect to the recently revived Rex's side. They are the first people to join him on his and Pyra's journey to reach Elysium. Eventually, it is revealed that Nia is a Blade who was merged with the corpse of her former Driver’s daughter. After the reveal, she can be freely switched between Blade and Driver forms. She even temporarily becomes the Blade to Rex during the final battle at the Cliffs of Moythra, due to Pyra and Mythra being unusable at the time.
As a background character
Nia makes an appearance as a background character along side her Blade, Dromarch on the currently unnamed stage that take place on Azurda.
As a costume
Nia's driver form appears as a costume for the Mii Brawler.
She also appears a spirit.